Mutant Herpes Simplex Viruses Comprising Nucleic Acid Encoding A Nitroreductase

Abstract

An herpes simplex virus wherein the herpes simplex virus genome comprises nucleic acid encoding a nitroreductase (NTR) is disclosed. Disclosed herpes simplex viruses are indicated to be useful in the treatment of cancer which may involve gene directed enzyme prodrug therapy.

1 . An oncolytic herpes simplex virus wherein the herpes simplex virus genome comprises nucleic acid encoding an heterologous nitroreductase (NTR),
 wherein the genome has an inactivating mutation in the RL1 locus such that the herpes simplex virus does not produce a functional ICP34.5 gene product,   and wherein the herpes simplex virus is a variant of one of HSV-1 strains 17 or F or HSV-2 strain HG52.   
     
     
         2 . The herpes simplex virus of  claim 1 , wherein the herpes simplex virus genome comprises nucleic acid encoding an heterologous NTR, wherein the genome has an inactivating mutation in the RL1 locus such that the herpes simplex virus does not produce a functional ICP34.5 gene product, and wherein the genome of the herpes simplex virus otherwise is the genome of HSV-1 strain 17 or F or HSV-2 strain HG52. 
     
     
         3 . The herpes simplex virus of  claim 1 , wherein the herpes simplex virus genome comprises a nucleic acid encoding an heterologous NTR, wherein the herpes simplex virus genome has an inactivating mutation in the RL1 locus such that the herpes simplex virus does not produce a functional ICP34.5 gene product, wherein the herpes simplex virus genome has a mutation in the ribonucleotide reductase gene, and wherein the herpes simplex genome otherwise is the genome of HSV-1 strain 17 or F or HSV-2 strain HG52. 
     
     
         4 . The herpes simplex virus of  claim 1 , wherein the herpes simplex virus is a variant of one of HSV-1 strains 17 or F. 
     
     
         5 . The herpes simplex virus of  claim 1  wherein the nitroreductase encoding nucleic acid comprises SEQ ID NO: 2, or a nucleic acid encoding the polypeptide of SEQ ID NO: 1, or a nucleic acid having at least 90% sequence identity to SEQ ID NO: 2 or to a nucleic acid encoding the polypeptide of SEQ ID NO: 1. 
     
     
         6 . A method for the treatment of a tumour involving lysing or killing tumour cells in a patient in need of treatment, the method comprising the steps of (i) administering to the patient the herpes simplex virus of  claim 1 , and (ii) administering to said patient a therapeutically effective amount of an NTR prodrug. 
     
     
         7 . The herpes simplex virus of  claim 1  wherein said herpes simplex virus genome further comprises a regulatory nucleotide sequence operably linked to said nucleic acid encoding NTR, wherein said regulatory nucleotide sequence has a role in controlling transcription of said NTR. 
     
     
         8 . The herpes simplex virus of  claim 1  wherein said nucleic acid is located in at least one RL1 locus of the herpes simplex virus genome. 
     
     
         9 . The herpes simplex virus of  claim 1  wherein said nucleic acid is located in, or overlaps, at least one of the ICP34.5 protein coding sequences of the herpes simplex virus genome. 
     
     
         10 . The herpes simplex virus of  claim 1  wherein the herpes simplex virus is a variant of HSV-1 strain 17 mutant 1716. 
     
     
         11 . The herpes simplex virus of  claim 1  in which all copies of the ICP34.5 gene present in the herpes simplex virus genome are disrupted such that the herpes simplex virus is incapable of producing a functional ICP34.5 gene product. 
     
     
         12 . The herpes simplex virus of  claim 1  which lacks only one expressible ICP34.5 gene. 
     
     
         13 . The herpes simplex virus of  claim 1  wherein said nucleic acid encoding the heterologous nitroreductase (NTR) forms part of a nucleic acid cassette integrated in the genome of said herpes simplex virus, said cassette encoding:
 (a) said nucleic acid encoding NTR; and nucleic acid encoding   (b) a ribosome binding site; and   (c) a marker,   
       wherein the nucleic acid encoding NTR is arranged upstream (5′) of the ribosome binding site and the ribosome binding site is arranged upstream (5′) of the marker. 
     
     
         14 . A medicament, pharmaceutical composition or vaccine comprising the herpes simplex virus of  claim 1 . 
     
     
         15 . A composition comprising the herpes simplex virus of  claim 1  and an NTR prodrug. 
     
     
         16 . A composition comprising the herpes simplex virus of  claim 1  and CB1954. 
     
     
         17 . A kit of parts comprising a first container having a quantity of the herpes simplex virus of  claim 1  and a second container having a quantity of an NTR prodrug. 
     
     
         18 . A method of expressing in vitro or in vivo a nitroreductase, said method comprising the step of infecting at least one cell or tissue of interest with the herpes simplex virus of  claim 1 , wherein the genome of said virus comprises a nucleic acid sequence encoding an heterologous nitroreductase in at least one of the long repeat regions (R L ), said nitroreductase operably linked to a transcription regulatory sequence. 
     
     
         19 . A method for the treatment of a tumour comprising the steps of:
 (i) administering to a patient in need of treatment a therapeutically effective amount of an oncolytic herpes simplex virus, wherein the genome of said virus comprises a nucleic acid sequence encoding an heterologous nitroreductase (NTR) in at least one of the long repeat regions (R L ), and wherein the genome has an inactivating mutation in the RL1 locus such that the herpes simplex virus does not produce a functional ICP34.5 gene product, and wherein the herpes simplex virus is a variant of one of HSV-1 strains 17 or F or HSV-2 strain HG52; and   (ii) administering to said patient a therapeutically effective amount of an NTR prodrug.   
     
     
         20 . An oncolytic herpes simplex virus, wherein the genome of said virus comprises a nucleic acid sequence encoding an heterologous nitroreductase (NTR) in at least one of the long repeat regions (R L ),
 wherein the genome has an inactivating mutation in the RL1 locus such that the herpes simplex virus does not produce a functional ICP34.5 gene product,   and wherein the herpes simplex virus is a variant of one of HSV-1 strains 17.